from __future__ import absolute_import, unicode_literals

import logging

from django.contrib import messages
from django.contrib.contenttypes.models import ContentType
from django.core.exceptions import PermissionDenied
from django.core.urlresolvers import reverse
from django.http import Http404, HttpResponseRedirect
from django.shortcuts import get_object_or_404, render_to_response
from django.template import RequestContext
from django.utils.translation import ugettext_lazy as _

from acls.models import AccessEntry
from common.utils import encapsulate
from permissions import Permission

from .forms import TransformationForm
from .models import Transformation
from .permissions import (
    permission_transformation_create, permission_transformation_delete,
    permission_transformation_edit, permission_transformation_view
)

logger = logging.getLogger(__name__)


def transformation_list(request, app_label, model, object_id):
    content_type = get_object_or_404(ContentType, app_label=app_label, model=model)

    try:
        content_object = content_type.get_object_for_this_type(pk=object_id)
    except content_type.model_class().DoesNotExist:
        raise Http404

    try:
        Permission.check_permissions(request.user, [permission_transformation_view])
    except PermissionDenied:
        AccessEntry.objects.check_access(permission_transformation_view, request.user, content_object)

    context = {
        'object_list': Transformation.objects.get_for_model(content_object),
        'content_object': content_object,
        'navigation_object_list': ['content_object'],
        'title': _('Transformations for: %s') % content_object,
        'extra_columns': [
            {'name': _('Order'), 'attribute': 'order'},
            {'name': _('Transformation'), 'attribute': encapsulate(lambda x: unicode(x))},
            {'name': _('Arguments'), 'attribute': 'arguments'}
        ],
        'hide_link': True,
        'hide_object': True,
    }
    return render_to_response(
        'appearance/generic_list.html', context, context_instance=RequestContext(request)
    )


def transformation_create(request, app_label, model, object_id):
    content_type = get_object_or_404(ContentType, app_label=app_label, model=model)

    try:
        content_object = content_type.get_object_for_this_type(pk=object_id)
    except content_type.model_class().DoesNotExist:
        raise Http404

    try:
        Permission.check_permissions(request.user, [permission_transformation_create])
    except PermissionDenied:
        AccessEntry.objects.check_access(permission_transformation_create, request.user, content_object)

    if request.method == 'POST':
        form = TransformationForm(request.POST, initial={'content_object': content_object})
        if form.is_valid():
            instance = form.save(commit=False)
            instance.content_object = content_object
            instance.save()
            messages.success(request, _('Transformation created successfully.'))
            return HttpResponseRedirect(reverse('converter:transformation_list', args=[app_label, model, object_id]))
    else:
        form = TransformationForm(initial={'content_object': content_object})

    return render_to_response('appearance/generic_form.html', {
        'form': form,
        'content_object': content_object,
        'navigation_object_list': ['content_object'],
        'title': _('Create new transformation for: %s') % content_object,
    }, context_instance=RequestContext(request))


def transformation_delete(request, object_id):
    transformation = get_object_or_404(Transformation, pk=object_id)

    try:
        Permission.check_permissions(request.user, [permission_transformation_delete])
    except PermissionDenied:
        AccessEntry.objects.check_access(permission_transformation_delete, request.user, transformation.content_object)

    if request.method == 'POST':
        transformation.delete()
        messages.success(request, _('Transformation deleted successfully.'))
        return HttpResponseRedirect(reverse('converter:transformation_list', args=[transformation.content_type.app_label, transformation.content_type.model, transformation.object_id]))

    return render_to_response('appearance/generic_confirm.html', {
        'content_object': transformation.content_object,
        'delete_view': True,
        'navigation_object_list': ['content_object', 'transformation'],
        'previous': reverse('converter:transformation_list', args=[transformation.content_type.app_label, transformation.content_type.model, transformation.object_id]),
        'title': _('Are you sure you wish to delete transformation "%(transformation)s" for: %(content_object)s') % {
            'transformation': transformation,
            'content_object': transformation.content_object},
        'transformation': transformation,
    }, context_instance=RequestContext(request))


def transformation_edit(request, object_id):
    transformation = get_object_or_404(Transformation, pk=object_id)

    try:
        Permission.check_permissions(request.user, [permission_transformation_edit])
    except PermissionDenied:
        AccessEntry.objects.check_access(permission_transformation_edit, request.user, transformation.content_object)

    if request.method == 'POST':
        form = TransformationForm(request.POST, instance=transformation)
        if form.is_valid():
            form.save()
            messages.success(request, _('Transformation edited successfully.'))
            return HttpResponseRedirect(reverse('converter:transformation_list', args=[transformation.content_type.app_label, transformation.content_type.model, transformation.object_id]))
    else:
        form = TransformationForm(instance=transformation)

    return render_to_response('appearance/generic_form.html', {
        'content_object': transformation.content_object,
        'form': form,
        'navigation_object_list': ['content_object', 'transformation'],
        'title': _('Edit transformation "%(transformation)s" for: %(content_object)s') % {
            'transformation': transformation,
            'content_object': transformation.content_object},
        'transformation': transformation,
    }, context_instance=RequestContext(request))